Dewar Flask

I wasn't quite sure which category this fit into, and if it's not this one, I'm sorry.

A couple of friends and I are great friends with our physics teacher. He is a great guy.
He likes to use LN2 alot, but to rent a dewar flask is fairly expensive he says and they're not always available.

A couple of friends and I are deciding to surprise him at the end of this year with a "you're awesome, thank you" gift at the end of this year. We were planning on getting him a Dewar Flask, about 4 L big. If anyone can help me out in picking out a good quality one for under around 400$ that would be great.

OK, I know you wanted to buy one, but here's what our physics teacher said he used to do. He'd go to a welding supply store to buy some LN2 and when asked if he had a Dewar flask he'd simply say no and they would let him sign for one and put down something like a $500 deposit. Sounds like a cool gift.

A couple of friends and I are deciding to surprise him at the end of this year with a "you're awesome, thank you" gift at the end of this year. We were planning on getting him a Dewar Flask, about 4 L big. If anyone can help me out in picking out a good quality one for under around 400$ that would be great.

Thanks.

With $400, you should be able to easily buy a nice, silvered glass 10L dewar if you don't mind buying used.

At the end of my last semester as an undergrad, I bought my aero professor a bottle of booze because I enjoyed his class the most of all the ones I had that semester. That was the only time I bought a teacher anything. It was more like, cheers, im done with this sh!t! Hes a good professor though, and a good guy. Hes pretty young for a professor, early 30's.